1. Field of the Invention
The present invention relates to a method for manufacturing unsupported metal lattice structures, and in particular to such a structure for generating a nickel lattice for use as a micro-flow sensor in gas analysis devices.
2. Description of the Prior Art
A method for manufacturing unsupported thin metal structures, such as lattices, is described in German Pat. No. 2,512,086 wherein an electroplated cover is applied to a carrier and the metal structures are built up by means of metal electro-deposition and are received in a carrying frame.
Such unsupported thin metal structures may be utilized as masks in electron lithography and x-ray shadow reproduction, or as thin film aperture diaphragms for corpuscular beam devices. A further use for such structures is to undertake resistance measurement in gas detecting devices, such devices requiring ultra-fine unsupported metal lattices. Because the structural dimensions of such lattices usually are in the micron range, manufacture and manipulation of such structures is extremely difficult.
An example of a conventional such lattice structure is shown in FIG. 1 which does in fact meet the high structural demands, but which is difficult to manufacture and as a result a high number of rejects occur in a typical manufacturing run. This conventional lattice structure is manufactured by means of soldering two separate nickel lattices between three ultrasonically bored glass laminae coated with glass solder. Nickel lattices 2 and 3 are thus produced at each side of a spacing glass 1. The module is closed by cover glasses 4 and 5. The bored opening is referenced at 6. The nickel lattices are galvano-plastically deposited on V2A steel plates and are drawn off as needed.